Improvement in sewing-machines



PATENT OEEICE.

CHARLES HALE, OF BANGOR, MAINE.

IMPROVEMENT IN SEWVING-MACHINES.

Specification forming part of Letters Patent No. 50,117, dated September26, 1865.

To all 'whom it may concern:

Beit known that I, CHARLES HALE, of Bangor, in the county of Penobscotand State of Maine, have invented a new and Improved Mode of PreventingSewing-Machines from Missing Stitches; and I do hereby declare that thefollowin g is afull, clear, and exact description thereof, referencebeing had to the accompanying drawings, and tothe letters of referencemarked thereon, in which- Figure 1 is a longitudinal vertical section ofmy improvement attached to a sewing-machine,'also shown in section. Fig.2 is a detached perspective view showing the operation of myimprovenient at the moment of forining the loop, or when the shuttleenters the loop. Fig. 8 is a detached perspective view, showing amisstitch and its cause. Fig. 4 is a longitudinal section of theair-pump. Fig. 5 is a detached perspective view showing the manner inwhich motive power is imparted to the air-pump from the sewing-machine,and Fig. 6 is an end view of the air-pump piston.

Similar letters of reference indicate corresponding parts in the severalfigures.

The nature of my invention consists in providing sewing-machines with anair-pump or other suitable mechanism by which a current of air iscreated, and by means of a tube or other conduit is conveyed to anorifice near the needle, and thence thrown upon that portion of thethread which forms the loop, deiecting it from the face of theshuttle-race (or needle) and beyond the line traversed by the point ofthe shuttle, therebyinsurin g the proper development of the loop, andpreventing the slack thread which forms the loop from bending or kinkingin the wrong direction and thus cans-5 ing a misst-itch.

A represents the table or bed-plate ot' the sewing-machine. B is thestandard. G is the arm through which passes the main shaft D.

- E is the pulley by which motion is imparted to is a crank fixed on thelower end of shaft A. h' and g are beVel-pinions.

The shaft D, being revolved. imparts motion to needle-bar d by means ofpin b, sliding in cam c. The shuttle receives its motion from itscarrier J, which is driven by pitman I, connected with the carrier att'. The pitman is connected at L with crank g, which receives its motionfrom vertical shaft A. which latter, by its pinion h meshing into piniong on shaft D, receives its motion from said shaft and communicates it tothe shuttle, as described, and also to the air-pump, as is hereinafterdescribed.

The sewing-machine, being well known, does not require a more particulardescription, some of the minor parts being omitted in the foregoing, itbeing intended only to show the principal movements connected with theimprovement, especially as the latter is not in its nalture confined tothis or any other machine; but being equally adapted to every kind andclass, its application is not intended to be confined in the claims tothe machine in connection with which it is herein described and shown.

M is the air-pump, which is secured to the under side of table A. N isthe piston. L is the pitman or connecting rod, connected with the pistonby pin u. K is a short shaft or pin passing through table A. On theupper end of this shaft is iiXed crank k, and ou the lower end crank Z.The pin hf, which connects crank g with the shuttle-pitman, projectsbelow the pitman a sufficient distance to bear against the edge ot'crank 7a, which is thereby carried round vsimultaneously with crank g;and crank Z being connected with the pump-pitman at on, the necessarymotion is thereby imparted to piston N. The piston is perforated with aseries of apertures, c', (shown in Figs. I and 6.) The valve a (shown inFigs. l and 4, and by dotted lines in Fig. 6) is formed of leather orother suitable elastic material. It overlaps and covers the aperturesc', and is secured to the piston by screw-cap b. i

i is the pump-head, which may be formed with the pump or separately, andsecured to it by male and female screws, as shown. It has anair-passage,f, leading through its center, and is formed witha nipple towhich is attached tube o at a'. The tube o passes up through table A atc, and thence, as shown in Fig. 2

compressed air which is being driven through aperture f into tube 0.

In sewing with machines, whether single or double thread, after theneedle has made its full descent all parts of the needle-thread are atfull tension; but when the needle begins its ascent, that portion oftheneedle-thread which is between the cloth and the needles eye begins toslacken,and should bend outward from the face of the race or from theneedle,and at the moment when the slack of the thread is sufcient toallow the proper development of the loop the stitch is formed, theaction ot' the machinery being adjusted to form the stitch at that pointin the movement; but, owing to a variety ot' causes, among which are thefrequent use of thread too' small for the needle, or thekinkynature ofsilk and twist, the thread, instead of bending outward from the needle,

.as shown at e, Fig. 2, bends or kinks in the opposite direction, asshown at e, Fig. 3, whereby the loop is not formed and a misstitchensues, thereby causing a serious defect, besides retarding the progressof the work. But by the use of my improvement a misstitch is rendered animpossibility, for the following reasons: The machine being put inmotion by the means already explained, the air-pump, Working as has beenshown, -forces a strong current of air through tube o and aperture Pupon the thread e, Fig. 2, at the moment when the thread slackens forthepurpose of forming the loop and stitch, by which means the slackthread is blown in a deflected line from the needle and face of theshuttle-race, thereby insuring the proper development of the loop andformation of the stitch, this being the result whether the machine usedbe a single or double thread machine, and whether a shuttle or any otherdevice be used for the purpose of forming the stitch. The blast shouldbe properly directed upon the thread, in order that it may not blow t-heloop in line with instead of out and away from the side of the race, orthe line traversed by the device which forms the stitch. I use the pumpM, as shown,for the purpose of throwing or forcing the blast of air uponthe loop; and I so adjust the movements of the pump to the machine thatthe full force ot the current ot' air is brought to bear upon the threadwhen the loop is being formed; but a variety of devices may be employedto produce the jet or blast of air, which devices may be operateddirectly by the machine or by any auxiliary or independent power, Whilethe current of air may be poured continuously upon the thread, or it maybe intermittent, as described above, and besides it may be thrown uponthe thread either through a single aperture or a plurality of apertures,and in the latter case the perforations may be direct or converging, asmay best accomplish the end in View.

What I claim as my invention, and desire to secure by Letters Patent,is-

1. The application to the needle-thread of sewing-machines of a currentor blast of air which will deect the thread in the right di rection forthe formation of the loop and stitch, as herein described and shown.

2. The combination of the air-pump M and tube 0, substantially as andfor the purpose specified.

CHARLES HALE. Witnesses:

T. W. PORTER, H. L. MITCHELL.

